Polycystic Ovarian Syndrome

PCOS is a common endocrine disorder in women of reproductive age, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology. It is associated with metabolic abnormalities and long-term reproductive and cardiovascular risks.

Definition

Epidemiology

Affects 6–20% of women of reproductive age depending on diagnostic criteria
Most common cause of anovulatory infertility
Prevalence higher in women with obesity and family history of PCOS
Ethnic variation exists: higher prevalence in South Asian women
Associated with increased risk of type 2 diabetes, metabolic syndrome, and cardiovascular disease

Etiology

Multifactorial: genetic predisposition, environmental factors, and lifestyle
Hyperinsulinemia and insulin resistance contribute to hyperandrogenism
Altered hypothalamic-pituitary-ovarian axis leading to increased LH and androgen production
Obesity exacerbates metabolic and reproductive manifestations
Potential role of chronic low-grade inflammation

Pathophysiology

Insulin resistance stimulates ovarian theca cells to produce excess androgens
Hyperandrogenism disrupts follicular development, causing anovulation
Polycystic ovarian morphology results from arrested follicle growth
Altered LH:FSH ratio (typically >2:1) contributes to androgen excess
Metabolic consequences include dyslipidemia, hypertension, and increased cardiovascular risk